JP2003266289A - Optical fiber end face polishing method and ferrule used therein - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attach a flange to a cylindrical ferrule having no flange to mount the ferrule on an end face polishing jig using the flange easily. <P>SOLUTION: A flange member 20 is attached to a predetermined position of outer periphery of a cylindrical ferrule main body 10 having no flange to which an optical fiber 15 is fixed. Next, the ferrule 1 is positioned and fixed to the end face polishing jig 30 using the flange member 20. Then, an end face of the optical fiber 15 is polished in a condition in which the ferrule 1 is positioned and fixed. The flange member 20 is removed from the ferrule 1 in which an end face polishing process ends. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for polishing an end face of an optical fiber fixed to a cylindrical ferrule without a flange used in various optical modules and the like, and a ferrule for polishing the end face of the optical fiber used therefor.

[0002]

2. Description of the Related Art Generally, an optical fiber is mirror-finished by inserting it into the center hole of a ferrule, fixing it with an adhesive, and polishing the end face together with the ferrule. The procedure is such that a polishing film having coarse abrasive grains to a polishing film having fine abrasive grains can be finished into a mirror surface through several polishing steps.

Further, for polishing the end face of such an optical fiber, a right angle polishing for forming a right angle end face orthogonal to the axis of the optical fiber into a flat surface or a spherical surface, and a predetermined angle with respect to an orthogonal face orthogonal to the axis of the optical fiber. There is tilt polishing in which a slanted end face is formed into a flat surface or a spherical surface.

By preparing a large number of such optical fibers, positioning and fixing the ferrules on an end face polishing jig, and setting the end face polishing jig on an optical fiber end face polishing machine, a large number of optical fibers are prepared. An optical fiber end face polishing machine capable of simultaneously polishing collectively is used.

[0005]

However, in order to position and fix the cylindrical ferrule without a flange to the end face polishing jig, a laborious work such as screwing the ferrules one by one is required. Moreover, with the recent increase in power, it is known that minute scratches on the end face of an optical fiber cause serious damage. Therefore, the repolishing process is frequently performed. In case of
Each time, the ferrule must be attached to the end face polishing jig by screwing.

Further, in the case of re-polishing, generally, finish polishing is performed by using a polishing film having fine abrasive grains. Therefore, in the case of right-angle polishing, it is difficult to precisely control the protruding amount of the ferrule tip from the end surface polishing jig by adjusting the screwing, and re-polishing efficiency is significantly impaired.

Further, in the case of tilt polishing, in addition to this, when the ferrule once removed from the end face polishing jig is reattached, an angular deviation is unavoidable, and even if the ferrule is marked. Even if a method such as attaching is taken, there is a problem that it is impossible to carry out re-polishing without any angle deviation.

An object of the present invention is to eliminate the problems of the above-mentioned conventional ones and to attach a flange to a cylindrical ferrule without a flange so that the ferrule can be easily attached to an end face polishing jig by using this flange. You can
Another object of the present invention is to provide an optical fiber end face polishing method that can be easily re-polished both in the case of right angle polishing and in the case of tilt polishing, and a ferrule used therefor.

[0009]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems. The invention according to claim 1 is a method for polishing an end face of an optical fiber fixed to a cylindrical ferrule without a flange. A step of attaching a flange member to a predetermined position on the outer periphery of the ferrule to which the fiber is fixed, a step of positioning and fixing the ferrule to an end face polishing jig using the flange member, and a step of fixing the end surface of the optical fiber in the fixed position. It is an optical fiber end surface polishing method including a step of polishing and a step of removing the flange member from the ferrule after the end surface polishing step.

According to a second aspect of the present invention, there is provided a method of polishing an end face of an optical fiber fixed to a cylindrical ferrule having no flange, wherein a circumferential reference is provided at a predetermined position on the outer circumference of the ferrule to which the optical fiber is fixed. By using the step of attaching a flange member having a reference portion indicating the orientation, and the flange member and the reference portion, an inclined end surface inclined at a predetermined angle with respect to an orthogonal surface orthogonal to the axis of the optical fiber can be obtained. In the end face polishing jig of the optical fiber end face polishing machine to be polished, the step of positioning and fixing the ferrule at the predetermined angle while maintaining the orientation that serves as the reference in the circumferential direction, and the end face of the optical fiber in the position and fixed state. An optical fiber end face polishing method comprising a step of polishing and a step of removing the flange member from the ferrule after the end surface polishing step. .

According to a third aspect of the present invention, in the invention according to the first or second aspect, the ferrule whose end face is polished in the end face polishing step is removed from the end face polishing jig to polish the end face of the optical fiber. When it is determined that re-polishing is necessary in the determination step, including the step of evaluating to determine whether re-polishing is necessary or not, after repeating the positioning and fixing step, the end surface polishing step and the determination step, the removal is performed. It is a method of polishing an end face of an optical fiber for executing a process.

According to a fourth aspect of the present invention, there is provided a ferrule body which is tubular without a flange and to which an optical fiber is fixed, and a flange member which is attached to an outer peripheral predetermined position of the ferrule body and which can be removed after polishing the end face of the optical fiber. Is a ferrule for polishing an optical fiber end face.

According to a fifth aspect of the invention, in the invention of the fourth aspect, the flange member is an optical fiber end face polishing ferrule made of a softer material than the material of the ferrule body.

According to a sixth aspect of the present invention, in the invention according to the fourth or fifth aspect, the flange member is oriented in a circumferential direction when the ferrule body is positioned and fixed to the end face polishing jig. Is a ferrule for polishing an end face of an optical fiber having a reference portion indicating.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. 1 (a) to 1 (c) are a plan view, a front view and a longitudinal sectional view showing an embodiment of an optical fiber end surface polishing ferrule according to the present invention. The optical fiber end surface polishing ferrule 1 is a ferrule. Body 10
And a flange member 20.

The ferrule body 10 is made of a material such as zirconia or glass, and has a substantially columnar ferrule portion 11 into which an optical fiber is inserted and fixed in a minute central hole (not shown).
And a substantially cylindrical outer cylinder 12 made of metal,
The hollow inside of the outer cylinder 12 is formed in a stepped shape with one end being enlarged, and the ferrule part 11 is attached to the enlarged part with its tip protruding from the outer cylinder 12.

The flange member 20 is the ferrule body 10.
Is formed into a substantially disk shape having a central hole 21 that is press-fitted into the outer cylinder 12, and is attached to the outer cylinder 12 at a predetermined position and after the end face of the optical fiber is polished, the ferrule body 10 is removed for use in an optical module or the like. It is possible, and the ferrule body 1 can be used to facilitate this removal.
In order not to damage 0, it is made of a material softer than the metal outer cylinder 12, such as plastic. Also,
The flange member 20 has a reference portion 22 for indicating a direction serving as a reference in the circumferential direction when the ferrule body 10 is positioned and fixed to an end surface polishing jig 30 described later, and the side surface of the reference portion 22 is It becomes the reference plane.

2 (a) to 2 (f) are schematic views showing various examples of the flange member 20 used in the ferrule 1 for polishing the end face of the optical fiber, and the flange member 2 shown in FIG. 2 (a).
In No. 0, the reference portion 22 is constituted by the segment-shaped notch 23 formed on one side of the disc-shaped flange member 20, and the notch surface serves as the reference surface. In addition, the flange member 20 shown in FIG. 2B has segment-shaped notches 23 on both sides.
The reference portions 22 are respectively configured by the above, and both of the notched surfaces can be used as the reference surface.

In the flange member 20 shown in FIG. 2 (c), a reference portion 22 is formed by a recess 24 formed on one side of the disk-shaped flange member 20, and the inner bottom surface of the recess 24 serves as a reference surface. In addition, the flange member 20 shown in FIG.
And the inner bottom surfaces of both recesses 24 can be used as reference surfaces.

In the flange member 20 shown in FIG. 2 (e), the reference portion 22 is formed by the convex portion 25 formed on one side of the disk-shaped flange member 20, and the outer top surface of the convex portion 25 serves as the reference surface. ing. In addition, the flange member 20 shown in FIG.
And the outer top surfaces of both convex portions 25 can be used as reference surfaces.

3 (a) to 3 (f) are schematic diagrams showing each step of the optical fiber end surface polishing method using the optical fiber end surface polishing ferrule 1, and the optical fiber end surface polishing method will be referred to with reference to FIG. explain.

First, as shown in FIG. 3A, the flange member 20 is attached to the ferrule body 10. Specifically, as shown in FIG. 4A, the ferrule body 10 is held by the fixed jig 19, while the flange member 20 is held by the movable jig 29, and the axes of the jigs 19 and 29 are kept constant. 4B, the center hole 21 of the flange member 20 is press-fitted into the outer cylinder 12 of the ferrule body 10 by moving the movable jig 29 closer to the fixed jig 19 to the position shown in FIG. 4B. The completed ferrule 1 for polishing the end face of an optical fiber is shown in FIG. The fixing jig 19 is the ferrule body 10
The mounting height h of the flange member 20 is determined by the height at which the flange member 20 is held.

Next, as shown in FIG. 3B, the optical fiber 15 is fixed to the ferrule 1 for polishing the end face of the optical fiber. That is, the optical fiber 15 is inserted from the outer cylinder 12 of the ferrule main body 10 into the hollow inside thereof, and the tip of the optical fiber 15 inserted into the minute center hole of the ferrule part 11 is slightly protruded from the tip of the ferrule part 11. Fix with an agent.

Next, as shown in FIG. 3C, the optical fiber end surface polishing ferrule 1 to which the optical fiber 15 is fixed is attached to an end surface polishing jig 30 for an optical fiber end surface polishing machine 50 described later. That is, by using the upper and lower surfaces of the flange member 20 and the reference surface of the reference portion 22 to perform positioning with respect to the positioning block 40 provided in the end surface polishing jig 30, the optical fiber end surface polishing ferrule 1 is moved to the end surface polishing jig 30. Secure it in place. In this case, the ferrule 1 for polishing the end face of the optical fiber is attached to the end face polishing jig 30 for positioning for polishing so that an inclined end face inclined at a predetermined angle with respect to a plane orthogonal to the axis of the optical fiber 15 is obtained. , Positioning and fixing at a predetermined angle while maintaining the reference direction in the circumferential direction.

Next, as shown in FIG. 3D, the end face polishing jig 30 is attached to a predetermined height of the optical fiber end face polishing machine 50, and the height is kept constant to keep the optical fiber end face polishing machine 50. By performing the polishing operation, the end face of the optical fiber 15 is polished (obliquely polished) together with the ferrule portion 11.

Next, as shown in FIG. 3E, the ferrule 1 for polishing the end face of the optical fiber which has been polished is removed from the end face polishing jig 30. Although not shown, the polishing state of the optical fiber end surface of the optical fiber end surface polishing ferrule 1 removed from the end surface polishing jig 30 is evaluated to determine whether re-polishing is necessary. Here, when the end face state of the optical fiber 15 has a scratch that cannot be ignored even if it is minute, and it is determined that re-polishing is necessary, the ferrule 1 for polishing the end face of the optical fiber 15 is attached to the end face polishing jig 30 again. Re-polishing is performed by operating the optical fiber end face polishing machine 50. This is repeated until it is determined that re-polishing is unnecessary.

Finally, as shown in FIG. 3 (f), the flange member 20 is removed, leaving the ferrule body 10 from the ferrule 1 for polishing the optical fiber end face. That is, the flange member 20 is removed from the outer cylinder 12 of the ferrule body 10 using an appropriate tool. At this time, the metal outer cylinder 1
Since the plastic flange member 20 is softer than the plastic flange member 2, the flange member 20 does not damage the outer cylinder 12.
Only the ferrule body 1 which can be easily removed
0 will be used for an optical module or the like.

FIGS. 5A to 5C are a plan view, a front view and a vertical sectional view showing another embodiment of an optical fiber end surface polishing ferrule according to the present invention. 101 is a flange member 120
Can be attached and detached from the side of the ferrule body 110.

Therefore, the ferrule body 110 is shown in FIG.
As shown in (d), the outer peripheral surface of the outer cylinder 112 is formed with a segmented notch 113 extending for a predetermined length from the end opposite to the mounting end of the ferrule part 111.

As shown in FIG. 5E, the central hole 121 of the flange member 120 is communicated with the outer periphery in the radial direction by a communication groove 126 which is slightly narrower than the diameter of the outer cylinder 112. Further, when the flange member 120 is mounted from the side of the ferrule body 110 on the side surface of the center hole 121 opposite to the communication groove 126, the segment-shaped notch 113 engages the flange member 120 from the side to allow relative positions in the circumferential direction. A linear engagement surface 127 that determines the distance is formed. Further, as shown in FIG. 5A, the flange member 120 is a reference portion 122 for indicating a reference orientation in the circumferential direction when the ferrule body 110 is positioned and fixed to the end surface polishing jig 30 described later. And a side surface of the reference portion 122 serves as a reference surface.
That is, in the flange member 120 shown in FIG. 5E, the reference portions 122 are formed by the recesses 124 on both sides, and the inner bottom surfaces of both the recesses 124 can be used as reference surfaces. Further, the flange member 1 shown in FIG.
The reference portion 122 of the disc-shaped flange member 20 is formed by a concave portion 124 formed on one side of the disc-shaped flange member 120.
The inner bottom surface of 24 serves as a reference surface.

The flange member 120 is different from the flange member 20 shown in FIGS. 1 and 2 in that the center hole 121 communicates with the communication groove 126 to the outer periphery in the radial direction.
The strength of holding force when attached to the ferrule body 110 is weak. Therefore, for example, MIM (Metal Injection Mo
It is preferable to use a metal powder formed by a metal powder injection molding sintering method called "lding". However, the present invention is not limited to this, and it is also possible to configure it as an appropriate plastic if necessary.

This optical fiber end face polishing ferrule 10
1 is the same as the ferrule 1 for polishing the end face of the optical fiber shown in FIG.
Although the flange member 120 can be mounted from the outside, the flange member 120 can also be mounted from the side of the ferrule body 110 by using the communication groove 126. Moreover, the mounting height h of the flange member 120 with respect to the ferrule body 110 is determined by engaging the engagement surface 127 with the end portion (lower end in the drawing) of the segment-shaped notch 113.

Further, when the flange member 120 is removed after the end surface polishing and the required re-polishing are completed, the communication groove 126 is formed.
By using, the ferrule for polishing optical fiber end face 1
It is possible to perform the removal work more easily than the above.

6 to 8 show an end surface polishing jig 30 for mounting the ferrule 1 for polishing the optical fiber end surface according to the present invention.
It is a figure which shows the polishing holder as a specific example of.

As shown in FIG. 6, the polishing holder 30 has a square plate-shaped holder body 31 having notches formed at the four corners.
And a plurality of (18 in the illustrated example) adapters 40 attached around the central round hole of the holder body 31, and a large number (18 in the illustrated example) for attaching the adapters 40 to the holder body 31. The mounting portion 32 of) is arranged annularly.

As shown in FIG. 7, each mounting portion 32 is formed as a substantially rectangular recess which is inclined in the same direction, and a through hole 33 through which the ferrule 1 for polishing the optical fiber end face is inserted at the center. A sleeve 34 having a is formed.

Each of the adapters 40 is a substantially rectangular bottom plate 41 that is placed on the bottom surface of the recess 32, and a cylindrical portion 42 that is inserted into the sleeve 34 is formed in the center of the bottom plate 41. The left and right ends of the bottom plate 41 are attached to the bottom surface of the recess 32 with a predetermined pressure by pressing springs 44 whose upper ends are locked by the washers 43.

As shown in FIG. 8, the upper surface of the cylindrical portion 42 is a supporting surface for supporting the lower surface of the flange member 20 of the ferrule 1 for polishing an optical fiber end face, and above the reference portion 22 of the flange member 20. A pair of claw portions 45 that are fitted to each other and determine the circumferential direction of the flange member 20 are provided so as to face each other. Since the height of the claw portion 45 is formed lower than the thickness (height) of the flange member 20, it does not protrude above the flange member 20. Tubular part 42
A screw is formed on the outer circumference of the bolt to form a bolt shape, and a supporting surface for supporting the upper surface of the flange member 20 downward is formed on the screwing member 46 having a nut to be screwed with the bolt, and the nut is screwed into the bolt. The optical fiber end face polishing ferrule 1 is fixed to the adapter 40 by sandwiching the flange member 20 between the support surfaces.

In this way, when the ferrule 1 for polishing the optical fiber end surface is mounted on the adapter 40, the ferrule 1 for polishing the optical fiber end surface is inserted into the through hole 33 of the holder body 31, and the tip thereof is held in the holder body 31. That is, a predetermined amount (for example, 0.5 mm or more) from the lower surface of the polishing holder 30.
The height of the adapter 40 is adjusted so as to project.

9 to 10 are views showing an optical fiber end face polishing machine 50 for polishing (obliquely polishing) the end face of the ferrule 1 for polishing the optical fiber end face, that is, the end face of the optical fiber 15.

The optical fiber end surface polishing machine 50 is provided with a turntable 53 that rotates and revolves while keeping horizontal in the center of a square base 52 located on the upper surface of the housing 51. The turntable 53 has a horizontal upper surface. The polishing pad 54
And the polishing film 55 is placed.

Four posts 60 are provided at the four corners of the base 52, and a pressure lever 65 is attached to each post 60. The pressure lever 6 on the right front side, not shown in FIG.
As for No. 5, the manner in which the polishing holder 30 is attached is shown in the plan view (a) and the vertical sectional view (b) of FIG. 11. That is, the polishing holder 30 is sized so that the arcuate edge portions of the four corners of the holder body 31 are placed on the cylindrical top portions 61 of the four posts 60. In addition, each pressurizing lever 65 is attached such that the cylinder portion 66 is inserted into the shaft portion 62 of the post 60 and is urged downward by the pressurizing spring 63. 67
You can change the direction. Therefore, when the polishing holder 30 is attached, the four pressure levers 65
Turn all the pressure pins 67 toward the outside by turning, and put the arc-shaped edges of the four corners of the holder body 31 on the cylindrical tops 61 of the four posts 60 from above, and turn the pressure levers 65 while pulling them up. , The pressure pins 67 are set so as to push the four corners of the holder body 31 from above.

Thus, when the polishing holder 30 is positioned and fixed to the four posts 60 of the optical fiber end surface polishing machine 50, the tip of the optical fiber end surface polishing ferrule 1 protruding from the lower surface of the polishing holder 30 is polished. Film 55
The height of each post 60 is adjusted so that the post 60 is pushed in a predetermined amount (for example, 0.1 mm).

As described above, in the optical fiber end surface polishing machine 50 using the polishing holder 30, a constant load is applied to each optical fiber end surface polishing ferrule 1 so that the tip of the ferrule 1 protrudes from the lower surface of the polishing holder 30 by a predetermined amount. Since it is configured with an independent loading method that can apply a force, it brings stable polishing results to all ferrules compared to, for example, a method in which the amount of protrusion of the ferrule tip from the end face polishing jig is adjusted for each ferrule. It is extremely excellent in

Although the flange member 20 is made of plastic in the above embodiment, the invention is not limited to this, and only the flange member 20 is removed without damaging the outer cylinder 12 of the ferrule body 10. Outer cylinder 1 to enable
Any material may be used as long as it is softer than the material of No. 2.

Further, in the above-described embodiment, the center hole 21 of the flange member 20 is press-fitted into the outer cylinder 12 of the ferrule body 10 to press the flange member 2 into the ferrule body 10.
However, the present invention is not limited to this, and the flange member 20 may be attached to the ferrule body 10 by using an appropriate fitting or screwing means.

[0047]

As described above, according to the present invention, a step of attaching a flange member to a predetermined position on the outer periphery of a cylindrical ferrule without a flange to which an optical fiber is fixed, and an end face polishing jig for a ferrule using this flange member Since it is configured to include a step of positioning and fixing the end face of the optical fiber in a positionally fixed state, and a step of removing the flange member from the ferrule after the end face polishing step, the ferrule using the flange member is used. Can be easily attached to the end face polishing jig. Further, both right-angle polishing and tilt polishing can be easily re-polished. Therefore, even if there is a minute scratch on the end face of the optical fiber, there is an effect that it can be repaired by re-polishing.

[Brief description of drawings]

1A is a plan view, FIG. 1B is a front view, and FIG. 1C is a vertical cross-sectional view showing an embodiment of a ferrule for polishing an end face of an optical fiber.

FIG. 2 is a schematic view showing various examples of a flange member used for a ferrule for polishing an end face of an optical fiber.

FIG. 3 is a schematic view showing each step of an optical fiber end surface polishing method using an optical fiber end surface polishing ferrule.

FIG. 4 is a schematic view showing a specific example of attaching a flange member to a ferrule body.

5 (a) is a plan view, FIG. 5 (b) is a front view and FIG. 5 (c) is a longitudinal sectional view showing another embodiment of the ferrule for polishing an optical fiber end face, and FIG. It is the schematic which shows an example.

FIG. 6A is a plan view and FIG. 6B is a right side view of a polishing holder to which a ferrule for polishing an end face of an optical fiber is attached.

FIG. 7 is a plan view (a), a front view (b), and a right side view (c) of an adapter in which an optical fiber end surface polishing ferrule is not attached.

FIG. 8 is (a) a plan view, (b) a front view and (c) a right side view of an adapter with an optical fiber end surface polishing ferrule attached.

FIG. 9 is a plan view of the optical fiber end surface polishing machine with a polishing holder attached.

FIG. 10 is a front view of the optical fiber end face polishing machine with no polishing holder attached.

11A is a plan view and FIG. 11B is a vertical cross-sectional view of a main part showing how a polishing holder is attached.

[Explanation of symbols]

1 Optical fiber end face polishing ferrule 10 Ferrule body 11 Ferrule part 12 outer cylinder 15 Optical fiber 19 Fixing jig 20 Flange member 21 Center hole 22 Standard part 23 Segmental notch (reference part) 24 Recessed part (reference part) 25 Convex part (reference part) 29 movable jig 30 End face polishing jig (polishing holder) 31 Holder body 32 Mounting part (recess) 33 through hole 34 Sleeve 40 adapter (positioning block) 41 Bottom plate 42 Cylindrical part 43 washer 44 Pressing spring 45 nails 46 screwing member 50 Optical fiber end face polishing machine 51 housing 52 base 53 turntable 54 polishing pad 55 Polishing film 60 posts 61 top of cylinder 62 Shaft 63 Pressure spring 65 Pressure lever 66 Tube 67 Pressure pin

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masami Suzuki             23 Stock Association at 286, Matsuhidai, Matsudo City, Chiba Prefecture             Shasei Engineering Lab F-term (reference) 2H038 CA22                 3C049 AA02 AB04 AB09 CA01 CB03                       CB04

Claims (6)

[Claims] 1. A method for polishing an end face of an optical fiber fixed to a cylindrical ferrule having no flange, comprising a step of attaching a flange member to a predetermined position on the outer circumference of the ferrule to which the optical fiber is fixed, and using the flange member. A step of positioning and fixing the ferrule to an end surface polishing jig, a step of polishing the end surface of the optical fiber in the position and fixed state, a step of removing the flange member from the ferrule after the end surface polishing step, An optical fiber end surface polishing method comprising: 2. A method for polishing an end face of an optical fiber fixed to a cylindrical ferrule without a flange, wherein a reference indicating a reference direction in the circumferential direction is provided at a predetermined position on the outer circumference of the ferrule to which the optical fiber is fixed. Attaching a flange member having a portion, and by using the flange member and the reference portion, an optical fiber end surface for polishing so that an inclined end surface inclined by a predetermined angle with respect to an orthogonal surface orthogonal to the axis of the optical fiber is obtained. In the end face polishing jig of the polishing machine, the step of positioning and fixing the ferrule at the predetermined angle while keeping the reference orientation in the circumferential direction, and the step of polishing the end face of the optical fiber in the fixed positioning state, And a step of removing the flange member from the ferrule after the end surface polishing step is completed. 3. The step of removing the ferrule whose end surface has been polished in the end surface polishing step from the end surface polishing jig and evaluating the polishing state of the end surface of the optical fiber to determine the necessity of re-polishing. 3. When it is determined that re-polishing is necessary, the positioning and fixing step, the end surface polishing step, and the determining step are repeated, and then the removing step is executed. Optical fiber end face polishing method. 4. A cylindrical ferrule body without a flange, to which an optical fiber is fixed, and a flange member attached to a predetermined position on the outer periphery of the ferrule body, the flange member being removable after polishing the end face of the optical fiber. A ferrule for polishing the end face of an optical fiber. 5. The ferrule for polishing an end face of an optical fiber according to claim 4, wherein the flange member is made of a softer material than the material of the ferrule body. 6. The flange member has a reference portion that indicates a direction that serves as a reference in the circumferential direction when the ferrule body is positioned and fixed to the end face polishing jig. The ferrule for polishing an end face of an optical fiber according to claim 5.